SpringBoot入门系列： JPA mysql(五)

一，准备工作，建立spring-boot-sample-mysql工程

1、http://start.spring.io/

     A、Artifact中输入spring-boot-sample-mysql

     B、勾选Web下的web

     C、勾选SQL下的JPA MYSQL

2、Eclips中导入工程spring-boot-sample-mysql

     A、解压快捷工程spring-boot-sample-mysql到某文件夹

     B、eclips中file->import->Import Existing Maven Projects–>Select Maven projects–>finish导入工程

3、工程导入之后，文件结构如下图

4、在包com.example下建立web文件夹

5、便于测试，引入spring-boot-sample-helloworld的HelloController及配置文件logback.xml

HelloController代码为

package com.example.web;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.web.bind.annotation.PathVariable;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;@RestControllerpublic class HelloController {    protected static Logger logger=LoggerFactory.getLogger(HelloController.class);    @RequestMapping("/")    public String helloworld(){        logger.debug("访问hello");        return "Hello world!";    }    @RequestMapping("/hello/{name}")    public String helloName(@PathVariable String name){        logger.debug("访问helloName,Name={}",name);        return "Hello "+name;    }}

logback.xml配置为

<configuration>      <!-- %m输出的信息,%p日志级别,%t线程名,%d日期,%c类的全名,,,, -->      <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">          <encoder>              <pattern>%d %p (%file:%line\)- %m%n</pattern>            <charset>GBK</charset>         </encoder>      </appender>      <appender name="baselog"          class="ch.qos.logback.core.rolling.RollingFileAppender">          <File>log/base.log</File>          <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">              <fileNamePattern>log/base.log.%d.i%</fileNamePattern>              <timeBasedFileNamingAndTriggeringPolicy  class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">                  <!-- or whenever the file size reaches 64 MB -->                  <maxFileSize>64 MB</maxFileSize>              </timeBasedFileNamingAndTriggeringPolicy>          </rollingPolicy>          <encoder>              <pattern>                  %d %p (%file:%line\)- %m%n            </pattern>              <charset>UTF-8</charset> <!-- 此处设置字符集 -->         </encoder>      </appender>      <root level="info">          <appender-ref ref="STDOUT" />      </root>      <logger name="com.example" level="DEBUG">          <appender-ref ref="baselog" />      </logger>  </configuration>

注：logback.xml文件位于src/main/resources下

6、启动工程，通过浏览器查看正确性

http://localhost:8080/

http://localhost:8080/hello/上帝

二，使用JPA,构建业务对象及访问库

1、在包com.example下建立domain文件夹

2、在domain中建立类Person

package com.example.domain;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.Id;@Entitypublic class Person {    @Id    @GeneratedValue    private Long id;    private String name;    private Integer age;    private String address;    public Person() {        super();    }    public Person(Long id, String name, Integer age, String address) {        super();        this.id = id;        this.name = name;        this.age = age;        this.address = address;    }    public Long getId() {        return id;    }    public void setId(Long id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public Integer getAge() {        return age;    }    public void setAge(Integer age) {        this.age = age;    }    public String getAddress() {        return address;    }    public void setAddress(String address) {        this.address = address;    }}

注意：构造函数

3、在包com.example下建立repository文件夹

4、在repository中建立接口PersonRepository

package com.example.repository;import java.util.List;import org.springframework.data.jpa.repository.JpaRepository;import org.springframework.data.jpa.repository.Query;import org.springframework.data.repository.query.Param;import org.springframework.stereotype.Repository;import com.example.domain.Person;@Repositorypublic interface PersonRepository extends JpaRepository<Person,Long> {    List<Person> findByName(String name);    List<Person> findByAddress(String address);    List<Person> findByNameAndAddress(String name,String address);    @Query("select p from Person p where p.name=:name and p.address=:address")    List<Person> withNameAndAddressQuery(@Param("name")String Name,@Param("address")String address);}

5、在web中建立DataController

package com.example.web;import java.util.List;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.data.domain.Page;import org.springframework.data.domain.PageRequest;import org.springframework.data.domain.Sort;import org.springframework.data.domain.Sort.Direction;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;import com.example.domain.Person;import com.example.repository.PersonRepository;@RestControllerpublic class DataController {    protected static Logger logger=LoggerFactory.getLogger(DataController.class);    @Autowired    PersonRepository personRepository;    @RequestMapping("/save")    public Person save(String name,String address,Integer age){        logger.debug("save 开始");        Person p=personRepository.save(new Person(null,name,age,address));        logger.debug("save 结束");        return p;    }    @RequestMapping("/q1")    public List<Person> q1(String address){        logger.debug("q1 开始");        logger.debug("q1 接收参数address={}",address);        List<Person> people=personRepository.findByAddress(address);        return people;    }    @RequestMapping("/q2")    public List<Person> q2(String name,String address){        logger.debug("q2 开始");        logger.debug("q2接收参数name={},address={}",name,address);        return personRepository.findByNameAndAddress(name, address);    }    @RequestMapping("/q3")    public List<Person> q3(String name,String address){        logger.debug("q3 开始");        logger.debug("q3接收参数name={},address={}",name,address);        return personRepository.withNameAndAddressQuery(name, address);    }    @RequestMapping("/sort")    public List<Person> sort(){        logger.debug("sort 开始");        List<Person> people=personRepository.findAll(new Sort(Direction.ASC,"age"));        return people;    }    @RequestMapping("/page")    public Page<Person> page(){        logger.debug("page 开始");        Page<Person> people=personRepository.findAll(new PageRequest(1,2));        return people;    }}

6、配置数据库连接，在application.properties（src/main/resources下）

spring.datasource.url=jdbc:mysql://192.168.56.201:3306/bootsample?useUnicode=true&characterEncoding=UTF-8
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.jackson.serialization.indent_output=true

7、运行测试

A、先保存数据

http://localhost:8080/save?name=aa&&address=北京&&age=1
http://localhost:8080/save?name=ab&&address=北京&&age=2
http://localhost:8080/save?name=cq1&&address=重庆&&age=50
http://localhost:8080/save?name=cq2&&address=重庆&&age=51

B、查询q1

http://localhost:8080/q1?address=北京

C、查询q2

http://localhost:8080/q2?address=北京&&name=aa

D、查询q3

http://localhost:8080/q3?address=北京&&name=aa

E、排序

http://localhost:8080/sort

F、分页

http://localhost:8080/page

运用hibernate访问mysql，基本也是老技术，只是用JPA简化了dao层代码，对于业务对象基本没有变化。